Embodiments relate to heating a liquid and, more particularly, to heating the liquid with a laser passing through the liquid to heat a heating device.
Water heating is a thermodynamic process that uses an energy source to heat water above its initial temperature. Fossil fuels such as, but not limited to, natural gas, liquefied petroleum gas, oil), or solid fuels are commonly used for heating water. These may be consumed directly or may produce electricity that, in turn, heats water. Electricity to heat water may also come from any other electrical source, such as nuclear power or renewable energy. Alternative energy such as solar energy, heat pumps, hot water heat recycling, and geothermal heating can also heat water, often in combination with backup systems powered by fossil fuels or electricity.
Water heaters have traditionally been tank type systems with a cylindrical vessel or container that keeps water continuously hot and ready to use once warmed by using electricity, gas or propane, a heat pump or a hybrid. When electricity is used, typically two heating elements are used to heat the water. Gas heat pumps use a burner to heat the water. A heat pump or hybrid uses energy from the air to heat the water. The heating elements in prior art water heaters, in both the electricity and gas versions, typically heat from the bottom, with the air rising through the tank and exiting from the top, allowing a fair amount of heat to be wasted. Tankless models also heat from the bottom, but the water flows through copper pipes. However, tankless models have been criticized as they do not store water and continually provide hot water to multiple locations in a facility relaying on the water heater to provide warm water.
Energy efficiencies of water heaters in residential use can vary greatly. Electric heaters tend to be slightly more efficient with a high recovery efficiency whereas gas fired heaters have a lower recovery efficiency than electric heaters as any remaining heat is lost with the flue gasses.
As part of the National Appliance Energy Conservation Act (NAECA), new minimum standards for efficiency of residential water heaters went into effect. All new gas storage tank water heaters with capacities smaller than fifty-five (55) US gallons (210 l; 46 imp gal) sold in the United States must now have an energy factor of at least sixty percent (60%) for 50-US-gallon units, higher for smaller units. This is an increase from the pre-2015 minimum standard of fifty-eight percent (58%) energy factor for a fifty (50) gallon gas unit. Electric storage tank water heaters with capacities less than 55 US gallons sold in the United States must have an energy factor of at least ninety-five percent (95%), which is an increase from the pre-2015 minimum standard of ninety percent (90%) for 50-gallon electric units.
The cost associated with operating a water heater varies based on the type of heating system used. For example, a typical electric water heater has two electrical elements which consume approximately forty-five hundred watts (4500 W) of electricity to heat the water. In comparison a hybrid water heater such as, but not limited to, the General Electric® GeoSpring™ water heater, uses approximately six hundred and seventy-two watts (672 W) to heat the water. Thus, a typical electric water heater costs about five hundred and eighty-five dollars a year to operate whereas a hybrid water heater costs about two hundred and twenty dollars a year to operate.
As the standards for efficiency increase, makers and users of water heaters would benefit from a water heater that exceeds these standards while also saving the user more money when using such a water heater than both electric and hybrid water heaters.